不同方式启动全自养脱氮组合工艺对比研究

A Comparative Study on the Combined Process of Total Autotrophic Nitrogen Removal with Different Starting Modes

为探究不同进水方式实现快速启动全自养脱氮工艺(CANON)处理高含氮有机废水的可行性,该研究分别采用直接高浓度进水和梯度浓度进水在2个完全相同的ABR-CSTR组合一体式反应器(1#、2#反应器)中启动反应,考察系统中全自养微生物活性和总氮去除性能。结果表明,在相同水力停留时间和间歇曝气的条件下,2组反应器均能在较短时间内成功启动,但相较于直接高浓度启动,逐步提高进水浓度更有利于脱氮功能菌的生长富集;1#反应器受到高负荷启动的限制,运行44 d总氮去除率(NRR)始终低于50%,但接种污泥经连续培养驯化后,最终NRR逐步升高并稳定在80%左右;2#反应器在梯度浓度进水状态下运行至第39天时,NRR达到88%,氨氮去除率达到99%,总氮去除负荷达到0.8634 kg/(m^(3)·d),反应器内壁出现较多红色污泥,成功启动CANON;微生物高通量测序表明,不同的进水模式下CANON系统中优势功能菌属均为Nitrosomonas和Candidatus Kuenenia。

To explore the feasibility of different influent modes to rapid start-up of full autotrophic denitrification process(CANON),high concentration influent and gradient concentration influent were used respectively to start the process in two identical ABR-CSTR integrated reactors(Reactor 1#,2#)to study the activity of autotrophic microbe and total nitrogen removal performance in the system.The results showed that when the system DO was controlled 0.3~0.6 mg/L,under the same hydraulic retention time(HRT)and intermittent aeration conditions,the two groups of reactors could be started successfully within a short time,but comparing with high concentrations,gradually improving the influent concentration was more advantageous to the growth and the enrichment of the function of denitrification bacteria.After 44 days of startup,the total nitrogen removal rate of the Reactor 1#was always below 50% as bacteria was limited by high loading operation.However,by subsequent stage of continuous operation,NRR was also went to 80% and stay stabilized.The NRR,NRE and NRL reached 88%,99% and 0.8634 kg/(m^(3)·d)respectively,when Reactor 2# was run at the gradient concentration of influent water on the 54 th day.A lot of red sludge appeared in the inner wall of the reactor,indicating that CANON was started successfully.High-throughput sequencing of microorganisms showed that under different influent modes,Nitrosomonas and Candidatus Kuenenia was the dominant functional bacteria in the CANON system under different influent modes.